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Franklin's X-ray diffraction, explanation of X-ray pattern.

Description:

How an X-ray diffraction pattern is created and how the DNA X-ray diffraction pattern can be interpreted to give the dimensions. (DNAi location: Code > Finding the Structure > piece of the puzzle > Franklin's X-ray)

Transcript:

This is the X-ray crystallograph pattern of DNA obtained by Rosalind Franklin and Raymond Gosling in 1952. It is know as the B-form. It was clearer than the other X-ray patterns because water was included in the DNA sample. Both James Watson and Francis Crick were struck by the simplicity and symmetry of this pattern. The distinctive "X" in this X-ray photo is the telltale pattern of a helix. Because the X-ray pattern is so regular, the dimensions of the helix must also be consistent. For example, the diameter of the helix stays the same..........